Is this the death rattle or something else?

[BulldogExplorer]

2001 Explorer Sport. I honestly have no idea when it started making this noise, had to have been well before 100k. I've had it for years and it has 130k on it now. I always assumed it was just a bad pulley. I bought it with about 58k miles on it and it was quiet back then.

On cold days when It's started it sounds fine at first(minus squeaking which I'm pretty sure is a pulley). When you put it into gear and the RPMs drop down it starts to do a rattle sound. It never makes the sound when it's over 1k RPM. I definitely don't feel anything or hear anything in the 2000+ range.

Ideas, doesn't seem like it matches the death rattle definition? I decided to go full out on maintenance this month since I let some things slide. New plugs/wires/tensioner/Idler/belt so I figured I'd try to find out what it was.

 

[99ex22]

Yeah that sounds like death rattle. does it go away after it's warmed up?

 

[mikekristine218]

Could it be a Catalyst Converter problem? My Jeep was famous for rattiling around 900-1500 RPM Range and no rattle 1500+. As soon as I replaced the Cat, no more rattle.

Good luck.

 

[2001ex]

my 4.0 sounds just like that and it has 78000 miles on it 2001 the ford dealer say it will run a long time sounding like this and from your truck has 130k I must have a lot of miles left